Page 40 - ebook fluid mechanics_finalize

FLUID MECHANICS

Exercise 1

1. With a figure, define the Pascal Law.

2. Explain with a diagram the working principle of a hydraulic jack.

Ans : [read the note of hydraulic jack principle]

3. Diameter of a large piston of jack hydraulic is 630mm three times bigger than diameter
of small piston. Large piston it use to support a load of 40kN. Calculate the force

needed at small piston if a large piston locates 2 m higher. Ans: 5070.87 N

4. A hydraulic jack used to carry up load. Oil is flowing a long pipe between two of
cylinder with relative density 0.9. The diameter each cylinder are 80 mm and 650 mm.

The smaller piston is 7 m above then large piston. Determine a force, F at small piston

needed to lift 4000kg mass located at large piston. Ans: 287.01N

5. A force, F of 900 N is applied to the smaller cylinder of a hydraulic jack. The area, a of

2
2
small piston is 22 cm and the area, A of larger pistons 250 cm . What load, W can be
lifted on the larger piston if,
i). The piston are at same level

ii). The large piston is 0.65 m below the smaller piston.

3
Consideration the mass density, ρ of the liquid in the jack hydraulic 10 kg/m
3
2
Ans: 10227.3N, 416.9kN/m

29